The invention relates generally to a magnetic actuator and more particularly to a magnetically driven actuator including a soft magnetic material such as an Fe-Co-V alloy particularly well suited for driving printing wires in an impact printer.
Fe-Co-V alloys are commonly employed in actuators and other devices when magnetic materials having high saturation magnetic flux density are required. Actuators commonly include soft magnetic material having a chemical composition of about 48-52% by weight cobalt, less than about 2.0% by weight vanadium, incidental impurities and the remainder iron. As the percentage of vanadium exceeds 2.0%, the DC magnetic properties of the magnetic material deteriorate. A common form of this alloy is 2V. PERMENDUR. This Fe-Co-V soft magnetic alloy exhibits favorable magnetic properties and favorable energy efficiency, compared to magnetic pure iron or magnetic silicon steel.
Conventional Fe-Co-V alloys employing less than 2% by weight vanadium have certain undesirable inherent properties. For example, when the magnetic material undergoes a large magnetic loss, the energy efficiency of the magnetic material deteriorates significantly. In addition, conventional Fe-Co-V alloys exhibit certain unsuitable magnetic properties when subjected to rapid current fluctuations.
Accordingly, it is desirable to provide improved magnetic material which can be included in an actuator for an impact printer or other device which overcomes the shortcomings of actuators formed of prior art magnetic material.